Photographic silver halide emulsion



Pnofroamrmc sILvER HALIDE EMuLsIoN Filed Dec. 23, 1939 sage.

l l l rw o a 0a INVENToRs Patented Sept. 16, 1941 l Y 2,256,163 I ruo'roGnArnlc sILvEa nALmE EMULsloN Karl Kumetat and Gustav Wilmanns, Wolfen, vKreis Bitterfeld, Germany, assignors to General Aniline & Film Corporation, New York, N. Y., a

corporation of Delaware Application December 23, 1939, Serial No. 310,826

y In Germany December 24, 1938 l 4 Claims.

The present invention relates to photographic silver halide emulsions.

In U. S. patent application Ser. No. 234,604, iiled October 12,l 1938, we have described, together with Oskar Riester, silver halide gelatine emulsions sensitized with sensitizing dyes, which on one or both sides of the trimethine chain contain an alkylated benzimidazole ring.

Further investigation has shown, that silver halide gelatine emulsions of improved sensitizing properties are obtained by incorporating therein sensitizing dyes of the above group, in which the nitrogen atom of the benzimidazole ring is substituted by an alkyl radical containing a trialkylammonium group. In this trialkylammonium group the nitrogen is pentavalent, the dyes are accordingly dibasic in character and have the following constitution:

H- hetero radical In this formula nis a whole number greater than 1 and R1, Rz, Ra the same or different alkyl radicals. X is an anion and the dotted line connecting the 2 carbon atoms of the right hand hetero radical indicates an atom grouping capable of completing the heterocyclic ring in the manner usual in cyanine dyestuff chemistry.

These dyes possess a greater water solubility and therefore yield photographic layers, which are not colored by a sensitizing dye after treatment in the photographic baths in an undesirable manner. They possess furthermore the same advantages compared with known dyestuffs as the sensitizers of the above named prior application.

The dyes are prepared according to the process described inv U. S. patent application Ser. No. 237,475, led October 28, 1938, assigned to the present assignee, by exchanging the quaternary N-alkyl-2-methylbenzimidazole for quaternary alkyl derivatives of N-(dialkylaminoalkyD-Z- methylbenzimidazole of the following formula.:

N- alkyl C CH;

The characters have the same meaning as in the preceding formula. This compound is rst prepared in its non-quaternary form as described in "Annalen 394, page for N-phenyl-Z-methylbenzimidazole.

C-CIIx /N\ R1 Rz This compound is rendered quaternary with 2 mols of an alkyl acid ester.

The following examples when taken with the accompanying self-explanatory drawing, depicting the sensitivity of a number of emulsions sensitized with dyestuis of the application serve to illustrate the invention:

Example I The dyestufi of 1,3,3-trimethylindoline-2- methene-w-aldehyde and 2,3-dimethyl-1-(trimethylammonium-propyl) -5-chlorobenzimidazoliummethylsulfate is-precipitated with 20% aqueous sodium perchlorate solution and has the following formula: J

'meayessensiuasshownmmgureiwitns maximum at 535 mp. Sensitizing range up to N I methene-w-aldehyde and 3-ethyL-2-methyl-1- H 1 benzimidazolium-eth'ylsulfate is precipitated with w 20% aqueous sodium perchlorate solution and 3 has the4 following formula: v

cin-cm I The dyes sensitize as shown in Figure 2 with a Imaximum at 548 mp. Sensitizing range up to j 580 mp.

i Example IV l The. dyestufl of l-ethyl-benzselenazoline-Z- lmethene-u-aldehyde and 2,3-dimethyl-1-(trilmethylammonium-,propyl 5 chlorobenzimidazo1iummethylsulfate is precipitated with 20% aqueous sodium perchlorate solution and has the following' formula:

Giri mi) l f Y llq/xlf-oihoH-OJKN El when. im

mayessensuzeasshnwnmmweawuha maximum at 560 mp. Sensitizing range up to aldehyde Example VI The dyestui! cf l-ethyl-thiazolidine-2-methammonium propy1) 5ch1orobenzimidazo1ium methylsulfate is precipitated with 20% aqueous sodium perchlorate solution and has the following formula: A

i (Img. o1 N B Cm Lemma-ouml: om N/ on. am 1o.-

El in. 'NwEl'ally The dyes sensitize` asshcwn in Figure 4 ''witli a maximum at 500 mp. Sensitizing range 45o-525 mp. y v

Example VII The dye oi 1ethyl-thiazolidine-Zfmethene-wand 3-ethyl-2-'methyl-1-(dimethyly zolium-ethylsulfate is precipitated with 20% 1 aqueous sodium perchlorate solution and has the following formula;

zal

The dyes sensitize with s maximum at 5,00 mp. e

Sensitizing range 450-525 mp.

' Example VIII The dyestui of l-ethyl-thiazolidine-Z-methene-w-aldehyde and 2,3-dimethy1-1-(trimethylammonium-propyl) -benzimidazolium-methylsulfate is precipitated with 20% aqueous sodium perchlorate solution and has the following formula: v

The dyes sensitize with a maximum at 495 my. Sensitizing range 450-515 mp.

Example IX 'I'he dye of i-ethyl-benzselenazoline-2-meth- `ene-w-aldehyde and l2,3-dimethyl-1 (trimethyl ammoniumproyl) -benzimidazolium-methylsulfate is precipitated with 20% aqueous sodium perchlorate solution and has the following formula:

sodium perchlorate and has the following formula:

The dyes sensitize with a maxium at 500 ma. Sensitizing range 450-520 ma.

Example XI The dye of l-ethyl-thiazolidine-2-methene-waldehyde and 2,6-dimethyl-3-ethyl-1-(dimethylethyl ammonium propyl) 5 chlorobenzimidazolium-ethylsulfate is precipitated with aqueous sodium perchlorate and has the following formula:

(IJrHl ci N CH CH '-cH=cH-oH=c H. 2010* 1f N (CHI im Hicl-'NcCHoi The dyes sensitize with a maximum at 500 ma. Sensitizing range 450-520 ma.

Example XII 'I'he dyestui of 1-ethyl-thiazolidine-2-methenew-aldehyde and 2,3-dimethyl-1`(trimethyl ammonium propy1) 5,6 dichlorobenzimidazolium-methylsulfate is precipitated with 20% aqueous sodium perchlorate and has the following formula.:

om ci N s CHi C1 N/Lo11=oH-c11=e\ /ilim C10...

N @ma ,H, 'NH3/Ha):

The dyes sensitize with a. maximum at 510 ma. Sensitizing range 4504530 ma.

Example XIII The dye of 1-ethyl-thiazolidine2-methene-waldehyde and 2,3-dimethyl-1;(trimethylammonium-propyl) -6 chlorobenzimidazolium methylsulfate is precipitated with 20% -aqueousv sodium perchlorate and has the following formula:

The dyes sensitize with a maximum at soo ma. Sensitizing range 45o-520 ma.

Example XIV The dye of 1ethylthiazolidine2-methene-waldehyde and 2,3,5-trimethyl-1-(trimethylammonium propyl) 6 chlorobenzimidazoliummethylsulfate is precipitated with 20% aqueous sodium perchlorate and has the following formula:

'I'he dyes sensitize with a maximum at 500 ma. Sensitizing range 45o-520 mia Example XV The dyestuff of 1ethyl-thiazolidine-Z-methene-w-aldehyde and 1-(dimethyl-ethylammonium-propy1-)2methyl 3 ethyl 5 chloro-6- isopropyl benzimidazolium ethylsulfate is precipitated with 20% aqueous sodium perchlorate and has the following formula:

The dyes sensitize with a maximum at 500 ma. Sensitizing range 450-520 ma.

Example XVI The dye of `1'-ethyl-thiazolidine-2-methene-waldehyde and 2,3-dimethyl-1(trimethylainmoni um propy1 6,7 dichlorobenzimidazoliummethylsulfate is precipitated with 20% aqueous sodium perchlorate and has the following for- The dyes sensitize with va maximum at 500 ma. Sensitizing range 450-520 ma.

Example XVII The dye of 1-ethyl-thiazolidine-2-methene-waldehyde and 2,3-dimethyl-1-(trimethyl-ammonium-propyl) -5 l triiiuormethyl benzimidazolium-methylsulfate is precipitated with 20% 4 allueous'sodium perchlorate and hasthe tollow- The Vdyessensitize with a maximum at'500 mn.

Bensitizing range 450420 ma.

I ene-u-aldehyde perchlorate and Example XIX The dye of 1,3,3trimethylindoline2methene u-aldehyde and L-(dimethylethylammoniumpropyl) 2,5-dimethyl 3 ethyl 6 chlorobenzimidazolium-ethylsuliate is precipitated with 20% aque'ous sodium perchlorate andhas the Ioli lowing formula:

@The dyes sensitize with a maximum at 545 mp. i Sensitizins range up to 570 mp.

Example XX The dye o! 1,3,3.5tetramethylindoline2 sodium perchlorate and propy1) -2,3,4 trimethyl benzimidazoliummethylsultate is-precipitated with 20%' aqueous The dyes sensmze with a maximum at 495 m.'

i i 3 methene-l-aldehyde and I (dimethyl-ethyl-ammonium-propyl-)Q- 2 methyl-3-ethyl5,6di chlorobenzimidazolium ethylsultate is precipi- 1 tated with 20% aqueous sodium has the following formula:`

Thedyesseminaires.showninr'igureswiuui` maximum at 555 mp. Sensitizing range up to 580m.

sodium perchlorate and has the following formula: f

H' clor- N Sensitizing range 4750-515 my..

Example XXIII aldehyde' and 1- (trimethylammoniumpropyl) 2,3,5-trimethyl benzimidazolium methylsulfate is precipitated with 20% aqueoussodium perchlorate and hasY the following formula:

da. r hill 'money1r The dyes sensitize with a. maximum at 500 mn.; Sensitizing range 450-520 mp.

Example XXIII w-aldehyde and 1-(dimethyl-ethyl-ammoniumbenzimidazolium-ethylsulfate is precipitated with 20% aqueous sodium perchlorate and has the following formula:

Cim C Hl 'I'hedyes sensitize with a maximum at 550 ma. I Sensitizing range up to 575 mp.

Example XXIV The dyestuxr of 1,a,3,5-tetiamethyl-mdolme-zmethene-u-aldehyde and l-(dimethyl-ethyl-amdichlorobenzimidazolium-ethylsulfate is precipitated with 20% aqueous sodium perchlorateand has the following formula:

The dyes sensitize as shown in Figure 6 with a 1- (trimethylammoniummaximumA at 560 my. Sensitizing range up to 585 mp.

The dyes are added either directly to the emulsions in the usual concentration or they may be incorporated in the emulsion by bathing the same in a solution of vthe dye. 'I'he dyes may also be employed in mixture with other carbocyanines. Especially mixtures with orthochromatia dyestui! corresponding to the following torcally sensitizing dyes such as pseudocyanines are mula:

useful. CH: CHI

We claim: Ri 1. A silver halide gelatine emulsion containing 5 1l; c an unsymmetrical benzimidazole trimethine cya- J: nine dye in which one of the nitrogen atom oi' CH=CHCH= the benzimidazole nucleus carries the radical N/ \N Rl l -(eHo.-i/ 1 NQR h\R|\ L, n' n being a whole number greater than i and wherein Ri. Ri, Ri is alkyl. X is en seid radice-l R1 ,3, ,R3 being alkyl, and n is a whole number greater than l.

2. A silver halide gelatin emuision containing 15 4. A silver helide'zeletin emulsion containing a dyestuii corresponding to the following foril dyetiin 001168320114111!! t0 the following 101- mula: mula:

1? 20 E', s om Leihen-endl; X U-Jl-ClkCH-Clk Ha N/ \N Y H0 L] I .Hol l 11,' 31 25 N R,

wherein nl, Ri, n.1 in alkyl. x is nn cid radicali wherein Ri. R2, Ra is alkyl, X is an acid radical and n is a whole number greater than 1. and n is a whole number greater than 1. 30 KARL KUMETAT.

3. A silver halide gelatine emulsion containing l GUBTAV WILMANNS. 

